Protein Synthesis

Connective Tissue Found everywhere in the body Includes the most abundant and widely distributed tissues Functions Binds body tissues together Supports the body Provides protection

Connective Tissue Characteristics Variations in blood supply Some vascularized Some avascular Extracellular matrix Non-living material that surrounds living cells

Extracellular Matrix Ground substance—mostly water along with adhesion proteins and polysaccharide molecules Fibers (3 types) Collagen Elastic Reticular

Connective Tissue Types Dense connective Tissue: Main matrix element is collagen fiber Fibroblasts: Locations Tendons— Ligaments— Dermis—

Tissue Repair (Wound Healing) Regeneration Replacement of destroyed tissue by the same kind of cells Fibrosis Repair by dense (fibrous) connective tissue (scar tissue) Determination of method Type of tissue damaged Severity of the injury

Events in Tissue Repair Capillaries become very permeable Introduce clotting proteins A clot walls off the injured area Formation of granulation tissue Growth of new capillaries Rebuild collagen fibers Regeneration of surface epithelium Scab detaches

Regeneration of Tissues Tissues that regenerate easily Epithelial tissue (skin and mucous membranes) Fibrous connective tissues and bone Tissues that regenerate poorly Skeletal muscle Tissues that are replaced largely with scar tissue Cardiac muscle Nervous tissue within the brain and spinal cord

Developmental Aspects of Tissue Epithelial tissue arises from all three primary germ layers Muscle and connective tissue arise from the mesoderm Nervous tissue arises from the ectoderm With old age, there is a decrease in mass and viability in most tissues